Ship drive with a driving engine and a directly driven propeller shaft

Abstract

A ship propulsion system in which the ship's propeller is connected with its propeller shaft directly to a drive mechanism. A thrust bearing in the drive mechanism receives directly the thrust of the propeller shaft. An auxiliary drive with an electrical machine is operable selectively as a motor or as a generator, and a coupling is provided between the electrical machine and transmission linkage in the auxiliary drive. A gear on the transmission surrounds the propeller shaft, and a flexible coupling connects the transmission to the propeller shaft. Mounted on a separate section of the propeller shaft between the transmission and the drive mechanism, is a shiftable coupling which is free of play and transmits torque from the drive mechanism to the propeller shaft as well as the thrust of the propeller shaft. An auxiliary thrust bearing is connected to the shiftable coupling and is actuated when the ship is in auxiliary or emergency operation during which the propeller shaft has a reduced thrust.

I claim: 
     
       1. A ship propulsion system comprising: drive means; a propeller with a propeller shaft connected directly to said drive means; a thrust bearing in said drive means for receiving directly thrust of said propeller shaft; auxiliary drive means having an electrical machine operable selectively as a motor or as a generator, said electrical machine being operated when electrical power is produced aboard ship; coupling means connected between said electrical machine and transmission means in said auxiliary drive means; gear means on said transmission means and surrounding said propeller shaft; a flexible coupling connecting said transmission means to said propeller shaft; a shiftable coupling mounted on a separate section of said propeller shaft between said transmission means and said drive means; said shiftable coupling being free of play and transmitting torque from said drive means to said propeller shaft and the thrust of said propeller shaft; an auxiliary thrust bearing free of play and connected to said shiftable coupling, said auxiliary thrust bearing being actuated when the ship is in auxiliary or emergency operation; said propeller shaft having a reduced thrust in said auxiliary or emergency operation transmitted through said auxiliary thrust bearing to said thrust bearing in said drive means in the ship's hull, said auxiliary drive means being operated when said electrical machine comprises a supplemental drive after said electrical machine is switched over to motor operation and said drive means is separated from said propeller shaft by disengagement of said shiftable coupling and actuating said auxiliary thrust bearing integral with said shiftable coupling. 
     
     
       2. A ship propulsion system as defined in claim 1, including a first flange connected to said drive means and also connected to an annular disc-shaped second flange through a threaded first connection; a bent third flange connected to said second flange through a threaded second connection, said second flange being also connected to said shiftable coupling through a threaded third connection; a pre-tensioned ring in said threaded second connection and a counter-nut connected to said pre-tensioned ring; adjusting means for releasing and tensioning said pre-tensioned ring and said counter-nut; said second flange and said third flange being mounted on a separate section of said propeller shaft; a tensioned collar on said separate section of said propeller shaft and being pressable to said second flange and said third flange free of play; said tensioned collar having ring-shaped discs between said collar and said second flange and between said collar and said third flange; said auxiliary thrust bearing being formed free of play by said second flange and said third flange. 
     
     
       3. A ship propulsion system as defined in claim 2, wherein in normal ship operation said first flange is connected to said second flange and said second flange is connected to said shiftable coupling, whereby said shiftable coupling is actuated and said counter-nut is tensioned. 
     
     
       4. A ship propulsion system as defined in claim 2, wherein in forward ship drive and in auxiliary or emergency operation said tensioned collar operates together with said second flange through a ring-shaped disc having tensioned blocks for transmitting reduced thrust of the propeller shaft, whereby said shiftable coupling is disengaged and said counter-nut is released. 
     
     
       5. A ship propulsion system as defined in claim 2, wherein in backward ship drive and in auxiliary or emergency operation said tensioned collar operates together with said third flange through a ring-shaped disc having tensioned blocks for transmitting reduced thrust of the propeller shaft, whereby said shiftable coupling is disengaged and said counter-nut is released. 
     
     
       6. A ship propulsion system as defined in claim 2, including another counter-nut for positioning said tensioned collar. 
     
     
       7. A ship propulsion system as defined in claim 2, wherein said first flange has a radially running first channel and said separate section of said propeller shaft has a second channel in the shaft's center axis, said first channel being connected to said second channel, said second channel having radial branches running to bearings lubricated on said separate section of said propeller shaft through said first and second channels in disengaged shiftable coupling and stationary first flange. 
     
     
       8. A ship propulsion system as defined in claim 7, wherein said first flange has another radially running channel communicating with an intermediate chamber between said first flange and said separate section of said propeller shaft. 
     
     
       9. A ship propulsion system as defined in claim 2, including a bearing on said separate section of said propeller-shaft near said first flange comprising a shaft-centering bearing. 
     
     
       10. A ship propulsion system comprising: drive means; a propeller with a propeller shaft connected directly to said drive means; a thrust bearing in said drive means for receiving directly thrust of said propeller shaft; auxiliary drive means having an electrical machine operable selectively as a motor or as a generator, said electrical machine being operated when electrical power is produced aboard ship; coupling means connected between said electrical machine and transmission means in said auxiliary drive means; gear means on said transmission means and surrounding said propeller shaft; a flexible coupling connecting said transmission means to said propeller shaft; a shiftable coupling mounted on a separate section of said propeller shaft between said transmission means and said drive means; said shiftable coupling being free of play and transmitting torque from said drive means to said propeller shaft and the thrust of said propeller shaft; an auxiliary thrust bearing free of play and connected to said shiftable coupling, said auxiliary thrust bearing being actuated when the ship is in auxiliary or emergency operation; said propeller shaft having a reduced thrust in said auxiliary or emergency operation transmitted through said auxiliary thrust bearing to said thrust bearing in said drive means in the ship's hull, said auxiliary drive means being operated when said electrical machine comprises a supplemental drive after said electrical machine is switched over to motor operation and said drive means is separated from said propeller shaft by disengagement of said shiftable coupling and actuating said auxiliary thrust bearing integral with said shiftable coupling; a first flange connected to said drive means and also connected to an annular disc-shaped second flange through a threaded first connection; a bent third flange connected to said second flange through a threaded second connection, said second flange being also connected to said shiftable coupling through a threaded third connection; a pre-tensioned ring in said threaded second connection and a counter-nut connected to said pre-tensioned ring; adjusting means for releasing and tensioning said pre-tensioned ring and said counter-nut; said second flange and said third flange being mounted on a separate section of said propeller shaft; a tensioned collar on said separate section of said propeller shaft and being pressable to said second flange and said third flange free of play; said tensioned collar having ring-shaped discs between said collar and said second flange and between said collar and said third flange; said auxiliary thrust bearing being formed free of play by said second flange and said third flange, in normal ship operation said first flange is connected to said second flange and said second flange is connected to said shiftable coupling, whereby said shiftable coupling is actuated and said counter-nut is tensioned, in forward ship drive and in auxiliary or emergency operation said tensioned collar operates together with said second flange through a ring-shaped disc having tensioned blocks for transmitting reduced thrust of the propeller shaft, whereby said shiftable coupling is disengaged and said counter-nut is released, in backward ship drive and in auxiliary or emergency operation said tensioned collar operates together with said third flange through a ring-shaped disc having tensioned blocks for transmitting reduced thrust of the propeller shaft, whereby said shiftable coupling is disengaged and said counter-nut is released; another counter-nut for positioning said tensioned collar, said first flange having a radially running first channel and said separate section of said propeller shaft has a second channel in the shaft's center axis, said first channel being connected to said second channel, said second channel having radial branches running to bearings lubricated on said separate section of said propeller shaft through said first and second channels in disengaged shiftable coupling and stationary first flange; a bearing on said separate section of said propeller shaft near said first flange comprising a shaft-centering bearing; said first flange having another radially running channel communicating with an intermediate chamber between said first flange and said separate section of said propeller shaft.